Safety device for use with tractors and the like



Oct. 26, 1954 SAFETY DEVICE 'r. A. D. WILSON 2,692,652

FOR USE WITH TRACTORS AND THE LIKE} Filed May 2, 1950 'INvEWMJ Mam/75mum/AER DONAL/J lu/zso v UNHTED STATES TENT QFFECE SAFETY DEVICE FOR USEWITH TRACTDRS AND THE LIKE Thomas Alexander Donald Wilson, Ashburton,Canterbury, New Zealand Application May 2, 1950, Serial No. 159,404

Claims priority, application New Zealand May 3, 1949 5 Claims. (Cl.mil-82) The invention relates to devices used with traccury 3 isretained at the bottom or" the bowl 2 tors and the like, whichexpression is intended and in the normal position thereof, the level ofover sloping or uneven ground surfaces, of the bring the tractor back toa safe position. angle of inclination or canting of the machines, 1Should the tractor continue to cent or tilt, the reaching a point ordegree approaching danger, mercury 3 then contacts the upper or secondring as regards capsizi'ng or overturning of the maand automaticallyswitches off the engine igchines, often with fatal results, and finally,should nition by grounding or shorting the ignition systhe warning gounheeded, to render the machine tem through the earthed mercury 3, andthereby inoperative against further travel, which would stopping theengine. accentuate the danger. In order to prevent the mercury 3 fromsplash- The invention resides in providing on the power ing, baflies areplaced across the bottom of the unit of a tractor or the like, anelectrical wiring bowl 2. These baflles enable the mercury to flowsystem which incorporates an earthed mercury quickly but preventpremature contacting or" the switch adapted firstly to operate a warningdevice, rings 5, 6.

and secondly to render said power unit inopera- To prevent the deviceoperating where the tive, upon the tractor or the like canting ortilttractor or the like may be travelling downhill, the ing beyond apredetermined point or degiee front portions of the rin s 5' 6' as shownin Fig In the accompanying drawing in conjunction i may be either coatedwith a non-conducting material I6, or said rings 5", 6" as shown in Fig.3 described, may be of horse shoe shape instead of circular, as Figure lis a wiring diagram illustrating the otherwise the device would operateno matter application of the invention to a motor power which way thetractor or the like canted.

unit provided with a magneto ignition, In order to restart the tractoior the like aftei igure 2 is a wiring diagram illustrating the 50 thedevice has stopped the engine, and until the application of theinvention to a diesel type motor tractor can be brought back b0 a safetyosition power un the device is electrically disconnected by a switchFig. 3 is a partial perspective view of the bowl or key 8 connected tothe magneto grounding with parts broken away illustrating amodificaterminal. The device can be attached to a tractor tion, and inany convenient position, but preferably at or Fig. 4 is a similar viewillustrating a further close to the magneto l. modification. As appliedto a diesel type motor power unit, The improved device will be furtherdescribed not provided with spark plug ignition, the bowl 2 as appliedto a tractor equipped with a magneto I with rings 5 and i and groundedmercury are (Figure l). The earthed mercury switch can M 3 or otheisuitable substance which will act simi- 9 and the ring 5 while a movablecoie solenoid laily thereto, as regards closing electric circuits i! isprovided in the circuit between th 11119 The bowl 2 preferably has a'cover 1'. and is 6 and the battery 9.

formed with sloping sides, and the bottom is Upon the tractor or thelike canting or tilting rounded to more effectually retain the mercury.sufficiently, the grounded mercury 3 or its sub- Within the bowl 2 aremetal rings 5, B spaced stitute in the bowl 2, contacts the ring 5 andapart at different levels around the sides of the closes the circuitthrough the lamp it, whereby bowl 2 above the mercury 3. The lower ring5 5c the latter wil be illumined.

is connected to a neon lamp 7 wired with a high Continued canting ortilting of the tractor or tension portion 14 going to the spark plug [5of the like to a point or degree which approaches ring 6 is alsoconnected with the ignition system or the like, results in the mercury 3contacting to short same to earth when required. The merring 6 wherebythe circuit throu h t [I is closed, and the latter is energised and actsto operate a fuel control cook 12 to the motor, so that the supply offuel to the latter is cut ofi and the motor is rendered inoperative.

What I do claim and desire to obtain by Letters Patent of the UnitedStates of America is:

1. A safety device for use in connection with vehicles including a powerunit and having an electrical wiring system comprising a grounde mercuryswitch in such wiring system, said mercury switch comprising a bowl andhaving inercury therein, two vertically spaced rings in said bowl ofelectrically conductive material, a warning device operatively connectedto the lower of said rings and means connected to the upper of saidrings adapted to render said power unit inoperative, said device ontilting first operating said warning device by contact of said mercurywith the lower of said rings and upon further tilting actuating saidmeans by contact of the mercury with the upper of said rings to rendersaid power unit in said vehicle inoperative.

2. A safety device as claimed in claim 1, said bowl consisting in amaterial non conductive of electricity and wherein the bottom portion ofsaid bowl is rounded, said rings completely encircling the interiorsurface of said bowl.

3. A safety device as claimed in claim 1, said bowl consisting in amaterial non-conductive of electricity and wherein the bottom portion ofsaid bowl is rounded, said rings being conductive only 4 partiallyaround the interior surface of said bowl thereby providing selectiveinoperative positions when said device is tilted.

4. A safety device as claimed in claim 1, and wherein said means torender said power unit inoperative comprises shortcircuiting meansconnected in the electrical wiring system.

5. A safety device as claimed in claim 1 and including a movable coresolenoid connected in said electrical wiring system, a fuel supply valvefor Said, power unit in proximity to said movable core and actuatablethereby, energizing means for said electrical wiring system, saidsolenoid being connected in said wiring system between said energizingmeans and the upper of said rings, whereby upon tilting and contactbeing made between said mercury and the upper of said rings saidsolenoid is actuated and said movable core contacts and moves said fuelsupply valve to said power unit thereby closing off the fuel supplythereto.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date Re. 19,234 Hendrickson July 10, 1934 1,867,278 Pensrum July12, 1932 2,075,040 Kieber Mar. 30, 1937 2,155,758 Hinde Apr. 25, 19392,192,262 Griesedieck Mar. 5, 1940

